为研究高燃温推进剂下喉栓式固体火箭发动机推力控制,设计同轴式变推力固体火箭发动机试验系统,以混合式直线步进电机作为喉栓驱动系统,采用组合动密封方式,利用高燃温高压强指数推进剂进行点火试验,实现了燃烧室压强从12.1～2MPa的调节。试验结果发现喉栓头部烧蚀严重,对压强调节影响较大,针对喉栓烧蚀问题提出了减轻烧蚀思路,通过闭环控制方式控制喉栓运动,增加喉栓直径以及合理选择推进剂等可降低喉栓烧蚀,提高压强控制精度。 In order to study the throat bolting solid rocket engine thrust control under high temperature and temperature propellant, a coaxial variable thrust solid rocket motor test system is designed. The hybrid linear stepping motor is used as the throat bolt driving system. The combined dynamic sealing method is adopted. Burning temperature and high pressure index propellant ignition test to achieve the combustion chamber pressure from 12.1 ~ 2MPa regulation. The test results showed that the head of the throat was ablated severely and had a great influence on the pressure regulation. In order to reduce the ablation of the throat, the idea of ​​reducing the ablation was put forward. The closed-loop control method was used to control the movement of the throat, increase the throat diameter and select the propellant rationally Can reduce the throat ablation, improve pressure control accuracy.